You mix sata and ssd disks within the same server? Read this: http://www.sebastien-han.fr/blog/2014/08/25/ceph-mix-sata-and-ssd-within-the-same-box/ When you have different pools for sata and ssd configure cache-pool: ceph osd tier add satapool ssdpool ceph osd tier cache-mode ssdpool writeback ceph osd pool set ssdpool hit_set_type bloom ceph osd pool set ssdpool hit_set_count 1 *In this example 80-85% of the cache pool is equal to 280GB* ceph osd pool set ssdpool target_max_bytes $((280*1024*1024*1024)) ceph osd tier set-overlay satapool ssdpool ceph osd pool set ssdpool hit_set_period 300 ceph osd pool set ssdpool cache_min_flush_age 300 # 10 minutes ceph osd pool set ssdpool cache_min_evict_age 1800 # 30 minutes ceph osd pool set ssdpool cache_target_dirty_ratio .4 ceph osd pool set ssdpool cache_target_full_ratio .8 Remember, that the current stable ceph 0.80.5 cache pool osds crashing when data is evicting to underlying storage pool. See http://tracker.ceph.com/issues/8982 2014-09-04 10:55 GMT+12:00 Andrei Mikhailovsky <andrei at arhont.com>: > Hello guys, > > I was wondering if someone could point me in the right direction of a step > by step guide on setting up a cache pool. I've seen the > http://ceph.com/docs/firefly/dev/cache-pool/. However, it has no > mentioning of the first steps that one need to take. > > For instance, I've got my ssd disks plugged into the osd servers. What do > I do next? How do i create the initial pool made just of these ssds and > promote it to the cache pool status. How do i choose the right cache pool > sizing, number of PGs, etc. > > Thanks > > Andrei > _______________________________________________ > ceph-users mailing list > ceph-users at lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.ceph.com/pipermail/ceph-users-ceph.com/attachments/20140904/e32871b7/attachment.htm>